Polishing tool

ABSTRACT

A polishing tool, to be driven in rotation by a driving machine about an axis of rotation, which is improved in respect of its handling and with regard to a more efficient work input, which polishing tool has a support body and a polishing body attached to the support body, wherein the polishing body comprises a number of first lamellae and at least a number of second lamellae, wherein the first lamellae comprise a polishing felt and the second lamellae comprise a nonwoven, wherein the nonwoven is formed substantially of synthetic fibers and wherein the nonwoven has a higher porosity than the polishing felt.

FIELD

The invention relates to a polishing tool, in particular which is to be driven in rotation by a machine tool, in particular a power tool, about an axis of rotation, which polishing tool has a support body and a polishing body attached to the support body, wherein the polishing body comprises a number of lamellae.

BACKGROUND

In polishing, surfaces are finely machined with a polishing tool which is moved relative to the workpiece. As a result of the energy input via the relative movement and the contact pressure, the surface of a workpiece, in particular a metallic workpiece, is machined without any appreciable change in the contour of the workpiece by smoothing out surface roughness, removing any impurities and, to a small degree, also by removing material from roughness peaks of the workpiece surface. In most cases there is thereby used a polishing agent which consists of unbonded mineral powder, mostly metal oxides with a high melting point and a low tendency to dissolve in water or oil. The mineral powder thereby forms particles with a geometrically undefined shape. For polishing purposes, the mineral powder is made into a paste or processed by mixing with heat-resistant fats or paraffins to form polishing pastes or polishing-agent suspensions. As a result of the particles, the pressure of the tool is transmitted point-wise via the very small contact area of the particles to the workpiece surface and results in local and brief flow processes, which lead to a reduction in the surface roughness.

For the decorative or technical fine-machining of surfaces there are conventionally used hand-operated machines having polishing tools, which do not have a workpiece-specific contour and are not intended for shaping the workpiece. Instead, polishing here serves in most cases to finish the surface for decorative purposes or to restore such a surface in the repair shop (e.g. polishing up painted parts, polishing out scratches), or for technical reasons, for example in mold making. Suitable hand-operated machines are in particular hand drills, right angle grinders or straight grinders.

In particular for use in vehicle bodies before and after painting there are additionally known so-called buffing wheels or buffing bells, in which the polishing body of the polishing tool consists of a stack of cotton cloths which are placed one on top of another and are quilted together according to the desired strength and which are arranged radially with respect to a bore of a work arbor or with respect to such a work arbor.

The fundamental advantage of such buffing wheels is the even lower transfer of the tool contour to the workpiece, so that, even in the case of highly sensitive surfaces, for example piano lacquers, marking can largely be ruled out. A disadvantage is the comparatively low efficiency.

U.S. Pat. No. 3,191,208 A discloses various buffing wheels, in which the hardness of the wheel is in some cases additionally increased by pleating the cotton cloth and in which, instead of a receiving opening for a mandrel, there is provided a metallic pronged pot onto whose prongs, which are arranged radially around a fastening opening for connection to a mandrel of a machine, the stack of cloths is threaded with or without additional stitching or quilting. The prongs are thereby longer than the stack of cloths is thick, so that, after the stack of cloths has been threaded onto the prongs, the ends of the prongs can be folded over in order to axially fix the stack of cloths.

WO 2002/018102 A1 discloses as felt polishing bodies, with reference to earlier prior art, solid felt polishing wheels, which can be used together with holding arbors for fastening the felt polishing wheels to machines. There are further disclosed a series of contoured felt polishing bodies, which range from small spherical shapes of the felt through various in some cases conical forms to cylindrical solid felt polishing bodies. These felt polishing bodies are also provided with shafts for mounting in conventional drill chucks.

WO 89/00092 discloses a polishing wheel made of a fibrous material and a use of such a polishing wheel for polishing watch cases. For this purpose, a comparatively narrow polishing wheel is described, the particular feature of which is described as being that it consists of a single solid fibrous material, wherein the wheel is cut transversely starting from the outer circumference in the direction toward the center. Three radial zones are thereby formed in the wheel. The outer zone has a plurality of such cuts. Only every second cut is continued into the zone lying radially further inward. The radially innermost zone has no such cuts. It is further described as being particularly preferred that these cuts do not extend exactly radially but are curved contrary to the direction of rotation and the tangents of the curved cut are inclined relative to the radial by an angle α, wherein the angle α increases from the outside to the inside. In connection with an exemplary embodiment, an inclination of 20° is indicated therein as a preferred value for the angle α. The inclination is such that the tangents point past the center of the disk in the direction of rotation, that is to say the slit radially outer parts of the polishing disk are pressed together by inertia on rotation and thus make the polishing disk particularly hard in the radial direction. The slits are thereby said to permit improved lateral (axial) movability of the disk. It is further described as being particularly preferred to use a comparatively hard felt for the polishing disk. As a result, a polishing disk is obtained that is very hard in the radial direction and at the same time comparatively flexible in the axial direction. Machining of the workpiece thereby takes place with the radially outer circumference of the tool.

In the grinding, that is to say the cutting surface machining, of workpieces with a tool having a geometrically undefined cutting edge, abrasives in the form of abrasive grains, which are bonded to the tool, are used. Depending on the flexibility of the grinding tool, the tool contour is transferred to the workpiece to a great or lesser degree during the machining of the workpiece surface.

In grinding tools with bonded grain, also referred to as bonded abrasives, the abrasive grains are embedded in a synthetic resin compound. These grinding tools are used in the form of grinding stones and grinding wheels for the shaping and surface machining of workpieces. Such grinding tools are rigid, which on the one hand facilitates the production of a surface contour but entails the problem that abrasive grain can break off in an uncontrolled manner and in larger fractions and thus leads to an uneven grinding pattern on the surface of the workpiece.

In contrast, there are coated abrasives. These are described in detail in DIN ISO 16057. Paper, woven fabric, polyester and fiber (vulcanized fiber) can be used as the carrier material for coated abrasives. These carrier materials make it possible to produce grinding tools which are evenly provided with abrasive grains of different grain sizes and abrasives. The abrasive grains are thereby fixed to the carrier material by means of synthetic resin bonding. Because the carrier material of the coated abrasives is flexible, such abrasives are also referred to as flexible abrasives. For the use of such grinding tools in sheet form, a supporting carrier part is required for use in grinding with machines, usually in the form of a so-called back-up pad, as is standardized in DIN ISO 15636. In order to improve the grinding efficiency and the tool life, it is known to arrange portions of support mesh with abrasive material with plastics bonding in the form of lamellae. Such a tool, which is also referred to in practice as a flap grinder, is described, for example, in DE 79 03 893 U1.

It is stated in EP 1 093 885 A1 that EP 922 535 A1 discloses a similar disk-type grinding tool in which resilient intermediate elements are to be arranged between the individual grinding lamellae. There is further known, for example from U.S. Pat. No. 4,517,773, a grinding tool in which the grinding lamellae are not configured to protrude perpendicularly from a disk-shaped base body but are arranged to protrude radially from a cylinder which is driven in rotation about its longitudinal axis. The individual grinding lamellae or grinding lamella bundles can here be stiffened on one side by a backing sheet so as to prevent the grinding lamellae from being deflected too greatly. These backing sheets are designed to be flexurally elastic but stiffer than the actual grinding lamellae. Gaps are provided between the individual grinding lamellae or grinding lamella bundles, which is said to result in an uneven grinding pattern specifically in the case of the machining of soft materials, for example wood.

EP 1 093 885 A1 proposes a disk-type grinding tool having grinding lamellae which are arranged radially with respect to the grinding tool axis, perpendicularly upright relative to the tool body. In order to ensure a constant spacing between the individual grinding lamellae, two intermediate elements, for example, are arranged between the grinding lamellae. The first intermediate element is to consist of a material which is elastic under pressure, and is not to come into contact with the side of the lamella that is not coated with abrasive. Between this intermediate element and the side of the lamella that is coated with abrasive there is arranged a further intermediate element. This intermediate element is preferably produced from a plastics material and has good bendability, but has higher wear resistance compared to the first intermediate element. By means of this arrangement, the wear behavior of the intermediate elements during operation of the grinding tool is said to be improved.

WO 2005/087436 A1 and EP 1 684 945 B1 disclose a lamellar grinding tool with a succession of overlapping lamellae containing abrasive grains, wherein these lamellae are formed alternately of grinding lamellae and compressible lamellae. Each grinding lamella is to lie with its operative part on a compressible lamella and be supported by the compressible lamella. It is also said to be possible to combine the lamellae into groups of lamellae of the type in question.

WO 2015/085211 A1 describes a coated abrasive material having a backing comprising a web or nonwoven of a polyester-based material impregnated with a phenolic resin, an acrylic resin, a urethane resin or a combination thereof, having an abrasive layer containing abrasive particles which covers the backing. U.S. Pat. No. 4,275,529 A discloses a lamellar grinding tool in which grinding lamellae are bundled together into stacks and intermediate layers of an abrasive nonwoven are arranged between adjacent grinding lamella bundles. Lamellar grinding tools with successive lamellae of abrasive nonwoven and abrasive cloth are known in the different abrasive combinations corundum/corundum, corundum/zirconium, carbide/corundum through being supplied by SKDS s.r.o., Luz̆any u Pr̆es̆tic, CZ, on the website SKDS.cz under the name “Lamelové kombinované kotouC̆e s upínací stopkou”, type designation BKC.

U.S. Pat. No. 6,582,289 and WO 00/30809 A1 disclose a flap grinding disk having first lamellae comprising a backing, a base bonding coat applied to the backing, a scattered layer of abrasive grain applied to the base bonding coat, and a top coat applied to the scattered layer of abrasive grain, and second lamellae consisting of a backing and a layer having grinding-active substances applied to the backing. Potassium fluoroborate, cryolite, calcium fluoride and chiolite are proposed as grinding-active substances. By means of such a configuration, it is said to be possible to produce a flap grinding disk with a reduced outlay in terms of production and material.

U.S. Pat. No. 5,752,876 A discloses a lamellar grinding disk in which the lamellae are arranged lying on the backing plate so as to overlap in a shingle-like manner. The lamellae consist of cotton or polyester fabric, on which abrasive particles are bonded by means of phenolic resin. The proposed arrangement is said to have the result that worn abrasive particles break off at the wear edges of the lamellae and the relatively flexible backing fabric which is then exposed quickly wears away and thus fresh abrasive grains are exposed, with which the grinding process can continuously be continued. Grinding marks caused by the tool being positioned and re-positioned after replacement of a worn or added grinding disk are thereby said to be reduced. Alternatively, it is proposed to replace the support fabric by nonwoven material, to which the mixture of resin and abrasive particles is to be applied. It is further also proposed to embed abrasive particles into the resin matrix of a backing plate made of glass-fiber-reinforced plastics material.

U.S. Pat. No. 3,529,385 A discloses a polishing brush which consists of strips of a nonwoven material, wherein the number of strips increases from the center of the support disk to the radially outer edge, so that the density of the strips is uniform or can even be adjusted so that it is higher at the radially outer edge.

DE 199 30 373 A1 discloses a porous polishing tool and a method for polishing a roller, which is said to allow a roller to be polished with satisfactory dimensional precision and thereby avoid feed marks and streaky print effects when the polished roller is to be used for printing.

DE 198 43 267 A1 discloses a polishing disk which has a short pile layer which is strongly bonded to a holding layer, and wherein a Velcro adhesive layer is attached to the back side of the polishing disk in order to removably attach the polishing disk to a corresponding polishing plate. It is described as an advantage that it is possible to remove the polishing disk from the polishing plate and wash it in domestic or industrial washing machines and thereby remove dried-on polishing agent and polishing dust. It is thereby said to be achieved that the polishing disk can be used several times.

WO 2002/018102 A1 and U.S. Pat. No. 7,794,309 disclose a lamellar polishing tool in which the polishing body is plurally subdivided and thereby forms a number of lamellae. For specific applications and use on stationary machines in series machining, it is further proposed to provide lamellae made of polishing felt of different densities. It is likewise disclosed therein to provide one or more intermediate layers between at least some of the felt lamellae in order to stiffen the tool. For the efficient machining of largely planar surfaces using a right angle grinder, it is advantageous to use a wheel as the supporting body and to arrange the felt lamellae on the axial end face of the wheel so that they protrude radially there beyond. With such an embodiment, it is also said to be possible to polish inner edge regions particularly well.

For use with the known polishing tools described hereinbefore, it is necessary to select a suitable polishing paste which is appropriate for the hardness of the felt material and the porosity thereof, wherein the nature of the added fat or oil is particularly important in order to avoid premature clogging of the polishing tool. Such premature clogging results in streaks and smears on the workpiece and can in an extreme case result in burn marks.

This problem is said to be avoided in the case of the polishing wheels described in German utility model specification DE-GM 1 940 005, in which an adapted polishing agent is to be integrated in a soft bond. To this end, the textile is to be impregnated with the polishing-agent preparation or such a preparation is to be embedded, for example by being enveloped in lengths of cloth. It is emphasized as being essential that the textile nature of such a polishing wheel is preserved, as in the known polishing wheels composed of flat or puffed-up layers of fabric.

Here too, as in the case of other polishing wheels, an appropriate contact pressure is to be maintained by the machinist in order on the one hand to achieve the desired polishing action and on the other hand to avoid overheating. Such overheating can lead to burn marks on the workpiece or to carbonization of the polishing felt, which in turn can result in scratches on the workpiece on future use of the polishing tool.

The polishing result is thus dependent on a certain degree of experience and practice on the part of the machinist, and on his experience in suitably selecting a polishing body of appropriate hardness and a polishing agent adapted to the material of the workpiece and to the polishing body.

The prior art thus describes multiple solutions for various improvements to grinding and polishing tools. Nevertheless, the proposed solutions have disadvantages of various kinds in respect of their handling, production or the economy of their use.

SUMMARY

Accordingly, the object of the invention is to provide a polishing tool which has improved properties in respect of its handling and with regard to a more efficient work input.

The object is achieved according to the invention by a polishing tool of the type mentioned at the beginning which is to be driven in rotation by a driving machine about an axis of rotation, which polishing tool has a support body and a polishing body attached to the support body, wherein the polishing body comprises a number of first lamellae and at least a number of second lamellae, wherein the first lamellae comprise a polishing felt and the second lamellae comprise a nonwoven, wherein the nonwoven is formed substantially of synthetic fibers and wherein the nonwoven has a higher porosity than the polishing felt.

The porosity of the nonwoven is thereby formed by the voids between the fibers. As a result, the nonwoven, during operation, takes up the polishing paste which is necessarily to be added and gradually releases it as the tool is used. During operation, the nonwoven thus acts as a depot for the polishing paste. By configuring the polishing body in the form of lamellae, the polishing agent can better be distributed over the surface of the polishing tool and the risk of clogging of the felt and thus of smearing on the workpiece, on the one hand, or of dry running of the polishing tool on the workpiece, on the other hand, can better be avoided.

As a result of the configuration according to the invention of a polishing tool, it is now possible to precision-grind and polish an unmachined workpiece surface in a single working step with only one tool. As a result of the depot action of the abrasive nonwoven for the polishing agent, it is in many cases also no longer necessary to interrupt the polishing process in order to add further polishing agent, whereby not only is a considerable time saving achieved, but impairments of the surface caused by interruptions, which require reworking, are also avoided. A polishing tool according to the invention thus permits quicker and more effective fine-machining of a surface of a workpiece for the majority of typical applications. The fine-machining of workpiece surfaces can thus be carried out substantially more economically with the polishing tool according to the invention than with the tools known hitherto.

Although, in particular for decorative purposes, a high-gloss polished surface, in some cases even a mirror finish, is occasionally desired as the result of the machining, satinized or matt polished surfaces are in most cases sufficient, in particular where technical demands are made of a polished surface, and in various materials, for example some stainless steels, a high-gloss polished finish is not possible at all owing to the structure of the material. With a polishing tool according to the invention, very finely satinized and matt polished surfaces have been produced with a very short machining time in one working step. Such surfaces are surfaces in which a business card of the usual form, when placed on the surface, is still readable via the reflection of the surface.

For the efficient machining of largely planar surfaces with a right angle grinder, it is advantageous if the support body is in the form of a support wheel. The support wheel can preferably be produced in the form of a synthetic-resin-bonded glass fiber disk or substantially from a plastics material, preferably a fiber-reinforced plastics material, from aluminum, a hard paper (fibrous material), a composite material or from steel.

The lamellae are preferably arranged on the axial end face of the wheel along the circumference of the support wheel, preferably protruding radially there beyond. With such an embodiment, inner edge regions can also be polished particularly well.

For a particularly high working efficiency, it is advantageous if the first and second lamellae are oriented substantially parallel to the axis of rotation. Such a polishing tool according to the invention can also be positioned over the entire surface for polishing, corresponding to a setting angle of 0°.

For some applications, for example where the workpiece has a pronounced curve or is otherwise contoured, it can be advantageous if the first and second lamellae are arranged inclined at an angle relative to the axis of rotation and the support wheel, preferably protruding radially beyond the edge of the support wheel.

For a good removal rate, for example when burrs are also to be removed in the fine-machining, it is expedient if the second lamellae comprise a nonwoven with abrasives bonded to fibers. For a good working result, a grain size of at least about 320 is thereby to be preferred, corresponding to a particle size of less than 50 μm.

For the machining of surfaces which tend to be contaminated, it can be advantageous if the second lamellae comprise a nonwoven without abrasives bonded to fibers. Where a low grinding power is required, it can be advantageous if the material of the synthetic fibers consists of a plastics material filled with an aluminum silicate powder.

For special applications, it can also be advantageous if the polishing body further comprises a number of third lamellae, wherein the second and third lamellae in each case comprise a nonwoven with and without abrasives bonded to fibers. The advantages of nonwoven lamellae with and without abrasives can thus be combined, and at the same time a particularly flexible polishing tool for highly contoured surfaces can be obtained.

Depending on the desired hardness of the polishing tool, it can be advantageous if the polishing body has first and second lamellae in a ratio of 1:1, 1:2 or 1:3.

In an embodiment of a polishing tool according to the invention that is economical in particular for series manufacture, the second lamellae of nonwoven are at least partially filled with a polishing paste. The polishing paste is thereby located in the voids between the fibers of the nonwoven. As a result, a polishing agent depot is formed, from which polishing agent is released continuously during the machining process. The amount of polishing agent can thereby be adjusted via a thickness and density of the nonwoven such that the polishing agent depot in the nonwoven lamellae is sufficient for the working life of the tool. The user of the tool is thus not concerned with questions of selecting the correct polishing agent and adding appropriate amounts of the polishing agent. Such a tool is particularly suitable for the repeated machining of larger surfaces even by semi-skilled personnel.

It is thereby particularly advantageous if the polishing body of the polishing tool is provided with a wrapping until it is used, which prevents the polishing agent from drying out. The wrapping can be, for example, in the form of a film or configured in the manner of a wax wrapping. The wrapping is usually to be removed by the user before the tool is used. The wrapping can also be formed by a packaging—optionally also a re-usable packaging—for one or more of the polishing tools according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in greater detail hereinbelow by means of exemplary embodiments which are shown in the accompanying drawings, in which:

FIG. 1 : shows a first embodiment of a polishing tool according to the invention in the form of a lamellar polishing wheel with upright lamellae in a perspective view;

FIG. 2 : shows the lamellar polishing wheel of FIG. 1 in a plan view of the polishing side;

FIG. 3 : shows a second embodiment of a polishing tool according to the invention in the form of a lamellar polishing wheel in a perspective view;

FIG. 4 : shows the lamellar polishing wheel of FIG. 3 in a plan view of the polishing side;

FIG. 5 : shows a third embodiment of a polishing tool according to the invention in the form of a lamellar polishing wheel with recumbent lamellae in a perspective view;

FIG. 6 : shows the lamellar polishing wheel of FIG. 5 in a plan view of the polishing side;

FIG. 7 : shows a fourth embodiment of a polishing tool according to the invention in the form of a lamellar polishing wheel in a perspective view;

FIG. 8 : shows the lamellar polishing wheel of FIG. 7 in a plan view of the polishing side;

FIG. 9 : shows a fifth embodiment of a polishing tool according to the invention in the form of a lamellar polishing wheel with upright lamellae in a perspective view;

FIG. 10 : shows the lamellar polishing wheel of FIG. 9 in a plan view of the polishing side;

FIG. 11 : shows a sixth embodiment of a polishing tool according to the invention in the form of a lamellar polishing wheel in a perspective view; and

FIG. 12 : shows the lamellar polishing wheel of FIG. 11 in a plan view of the polishing side.

DETAILED DESCRIPTION

The polishing tool according to the invention shown in the figures, designated generally 1, is configured to be driven in rotation by a machine tool about an axis of rotation 2. The polishing tool 1 has a polishing body which comprises a number of first lamellae 3 and at least a number of second lamellae 4. The first and second lamellae 3, 4 are fastened to a support wheel 5 as a support body. The support wheel 5 has a holding surface which is formed rotationally symmetrically to the axis of rotation 2 of the polishing tool 1 and to which the lamella 3, 4 are fastened, for example by means of a synthetic resin adhesive. The holding surface is arranged on the support wheel 5 axially at the end face.

The first lamellae 3 are produced from a polishing felt. The felt material of the first lamellae 3 can comprise conventional polishing felts, for example and preferably polishing felt with a content of pure wool (animal hair) of at least about 30% and with a hardness of preferably from 0.14 to 0.68 (W4 to H5) according to DIN 61200. In particular substantially fewer polishing residues thereby accumulate on the workpiece than with other polishing materials.

The second lamellae 4 comprise a nonwoven, wherein the nonwoven is formed substantially of synthetic fibers. The nonwoven has a higher porosity than the polishing felt. Abrasive nonwovens consist of synthetic fibers, mostly nylon, polyester or mixtures thereof. Depending on the processing, abrasive nonwovens of different elasticity and strength are thereby obtained. A method for producing an abrasive nonwoven with abrasives in the form of abrasive grains bonded to the fibers is known, for example, from WO 2017/072293 A1 and US 2018/0326556 A1. The porosity of the nonwoven is formed by the relatively large voids between the fibers.

During operation, the nonwoven thus takes up the polishing paste which is necessarily to be added and gradually releases it as the tool is used. The nonwoven thus acts during operation as a depot for the polishing paste. By configuring the polishing body in the form of lamellae, the polishing agent can better be distributed over the surface of the polishing tool and the risk of clogging of the felt and thus of smearing on the workpiece, on the one hand, or of dry running of the polishing tool on the workpiece, on the other hand, can better be avoided.

As a result of the configuration according to the invention of a polishing tool, it is now possible to precision-grind and polish an unmachined workpiece surface in a single working step with only one tool. As a result of the depot action of the abrasive nonwoven for the polishing agent, it is in many cases also no longer necessary to interrupt the polishing process in order to add further polishing agent, whereby not only is a considerable time saving achieved, but impairments of the surface caused by interruptions, which require reworking, are also avoided. A polishing tool according to the invention thus permits quicker and more effective fine-machining of a surface of a workpiece for the majority of typical applications. The fine-machining of workpiece surfaces can thus be carried out substantially more economically with the polishing tool according to the invention than with the tools known hitherto.

Although, in particular for decorative purposes, a high-gloss polished surface, in some cases even a mirror finish, is occasionally desired as the result of the machining, satinized or matt polished surfaces are in most cases sufficient, in particular where technical demands are made of a polished surface, and in various materials, for example some stainless steels, a high-gloss polished finish is not possible at all owing to the structure of the material. With a polishing tool according to the invention, very finely satinized and matt polished surfaces have been produced with a very short machining time in one working step. Such surfaces are surfaces in which a business card of the usual form, when placed on the surface, is still readable via the reflection of the surface.

The support wheel 5 can expediently be produced in the form of a resin-bonded glass-fiber disk or from a plastics material, preferably a fiber-reinforced plastics material, from aluminum, a hard paper (fibrous material) or from steel. The support wheel 5 is expediently configured with a depressed center as shown in the figures. In the case of highly contoured workpieces, the working distance between the driving machine and the workpiece surface can thereby be increased, on the other hand such a more rigid form of the support wheel 5 counteracts wobbling of the polishing tool 1.

The embodiments of a polishing tool 1 according to the invention that are shown in FIGS. 3, 4, 7, 8, 11 and 12 have a support wheel 5 with a hole 6 for receiving a conventional arbor for connection to a driving machine. Where the support wheel 5 is produced from a fiber-reinforced plastics material, the edge of the hole 6 is expediently reinforced with a metal eye 7 in order to ensure a secure centric fit. A diameter of the hole 6 of 22.23 mm is appropriate for many right angle grinders.

However, in conjunction with conventional power tools, such as right angle grinders, it is advantageous for a quick and simple tool change to provide a carrier element 8 in a central region of the support wheel 5 and to arrange a single- or multi-start screw or nut thread in the carrier element 8. A terminal nut thread of size M14 or ⅝-11″ would be particularly suitable here. Such an embodiment of a polishing tool 1 according to the invention is shown in FIGS. 1, 2, 5, 6, 9 and 10 .

For a particularly high working efficiency, it is advantageous if the first and second lamellae 3, 4 are oriented substantially parallel to the axis of rotation 2, that is to say upright on the axial end face of the support wheel 5. The lamellae 3, 4 are arranged along the circumference of the support wheel 5, preferably protruding radially there beyond. This can be seen particularly clearly in FIGS. 1 to 4 and 9 to 12 . Such a polishing tool according to the invention can also be positioned over the entire surface for polishing, corresponding to a setting angle of 0°.

For some applications, for example where a workpiece has a pronounced curve or is otherwise contoured, it can be advantageous if the first and second lamellae 3, 4 are arranged inclined at an angle relative to the axis of rotation 2 and the support wheel 5, likewise preferably protruding radially beyond the edge of the support wheel 5. Such an arrangement is also referred to as “recumbent”. Embodiments with such an arrangement of the lamellae 3, 4 are shown in FIGS. 5 to 8 .

FIGS. 1, 3, 5, 7, 9 and 11 show a perspective view of the embodiments of a polishing tool 1 according to the invention viewed from the driving machine side. FIGS. 2, 4, 6, 8, 10 and 12 show a plan view of the embodiments of a polishing tool 1 according to the invention viewed from the workpiece side.

Owing to the radial protruding length 10 of the lamellae 3, 4 beyond the edge of the support wheel 5, inner edge regions can also be polished particularly well with such an embodiment, because this polishing tool 1 reaches into the corners.

It has been found to be expedient to provide a thickness of the lamellae 3, 4 of from about 1 mm to about 20 mm, preferably in the range of from about 3 mm to about 10 mm. In order to adjust the desired properties of a polishing tool 1 according to the invention, the thickness of the first lamellae 3 and of the second lamellae 4 can be adjusted Thinner first lamellae 3 in conjunction with thicker second lamellae 4 result in higher agressivity, that is to say a higher removal rate.

For a good removal rate, for example when burrs are also to be removed in the fine-machining, it is expedient if the second lamellae 4 comprise a nonwoven with abrasives bonded to fibers. For a good working result, a grain size of at least about P320 according to FEPA or finer is to be preferred, corresponding to a particle size of less than about 50 μm.

For the machining of surfaces which tend to be contaminated, it can be advantageous if the second lamellae 4 comprise a nonwoven without abrasives bonded to fibers. Where a low grinding power is required, it can be advantageous if the material of the synthetic fibers consists of a plastics material filled with an aluminum silicate powder.

For special applications, it can also be advantageous if the polishing body further comprises a number of third lamellae 9, wherein the second and third lamellae 4, 9 in each case comprise a nonwoven with and without abrasives bonded to fibers. The advantages of nonwoven lamellae with and without abrasives can thus be combined, and at the same time a particularly flexible polishing tool 1 for highly contoured surfaces can be obtained. Such an embodiment is to be seen in FIGS. 9 and 10 .

Depending on the desired hardness of the polishing tool, it can be advantageous if the polishing body has first and second lamellae 3, 4 in a ratio of 1:1, 1:2 or 1:3. An embodiment of a polishing tool 1 according to the invention with first and second lamellae 3, 4 in a ratio of 1:2 is shown in FIGS. 11 and 12 .

In an embodiment of a polishing tool 1 according to the invention that is economical in particular for series manufacture, the second lamellae 4 of nonwoven are at least partially filled with a polishing paste. The polishing paste is thereby located in the voids between the fibers of the nonwoven. As a result, a polishing agent depot is formed, from which polishing agent is released continuously during the machining process. The amount of polishing agent can thereby be adjusted via a thickness and density of the nonwoven such that the polishing agent depot in the nonwoven lamellae is sufficient for the working life of the tool. The user of the polishing tool 1 according to the invention is thus not concerned with questions of selecting the correct polishing agent and adding appropriate amounts of the polishing agent. Such a polishing tool 1 according to the invention is particularly suitable for the repeated machining of larger surfaces even by semi-skilled personnel.

It is thereby particularly advantageous if the polishing body of the polishing tool 1 is provided with a wrapping until it is used, which prevents the polishing agent from drying out. The wrapping can be, for example, in the form of a film or configured in the manner of a wax wrapping. The wrapping is usually to be removed by the user before the tool 1 is used. The wrapping can also be formed by a packaging—optionally also a re-usable packaging—for one or more of the polishing tools 1 according to the invention.

LIST OF REFERENCE NUMERALS

-   1 polishing tool -   2 axis of rotation -   3 first lamellae -   4 second lamellae -   5 support wheel -   6 hole -   7 metal eye -   8 carrier element -   9 third lamellae -   10 protruding length 

What is claimed is: 1-10. (canceled)
 11. A polishing tool which is to be driven in rotation by a driving machine about an axis of rotation, the polishing tool comprising: a support body, and a polishing body attached to the support body, wherein the polishing body comprises a number of first lamellae and at least a number of second lamellae, wherein the first lamellae comprise a polishing felt and the second lamellae comprise a nonwoven, wherein the nonwoven is formed substantially of synthetic fibers, and wherein the nonwoven has a higher porosity than the polishing felt.
 12. The polishing tool as claimed in claim 11, wherein the support body is in a form of a support wheel.
 13. The polishing tool as claimed in claim 11, wherein the first lamellae and the second lamellae are oriented substantially parallel to the axis of rotation.
 14. The polishing tool as claimed in claim 12, wherein the first lamellae and the second lamellae are arranged inclined at an angle relative to the axis of rotation and the support wheel.
 15. The polishing tool as claimed in claim 11, wherein the second lamellae comprise a nonwoven with abrasive bonded to fibers.
 16. The polishing tool as claimed in claim 15, wherein the abrasive bonded to fibers has a grain size of at least
 320. 17. The polishing tool as claimed in claim 11, wherein the second lamellae comprise a nonwoven without abrasive bonded to fibers.
 18. The polishing tool as claimed in claim 11, wherein: the polishing body further comprises a number of third lamellae, and the second and third lamellae each comprise a nonwoven with and without abrasive bonded to fibers.
 19. The polishing tool as claimed in claim 18, wherein the abrasive bonded to fibers has a grain size of at least
 320. 20. The polishing tool as claimed in claim 11, wherein the polishing body has the first lamellae and the second lamellae in a ratio of 1:1, 1:2 or 1:3.
 21. The polishing tool as claimed in claim 11, wherein at least the second lamellae of nonwoven are at least partially filled with a polishing paste. 